Accumulating animal studies have demonstrated the harmful contribution of ambient air pollution (AP) to metabolic dysfunction-associated fatty liver disease (MAFLD), but corresponding epidemiological evidence is limited. We examined the associations between long-term AP exposure and MAFLD prevalence in a Chinese population. We conducted a cross-sectional study of 90,086 participants recruited in China from 2018 to 2019. MAFLD was assessed based on radiologically diagnosed hepatic steatosis and the presence of overweight/obese status, diabetes mellitus, or metabolic dysregulation. Residence-specific levels of air pollutants, including particulate matter with aerodynamic diameters of ≤1 μm (PM₁), ≤2.5 μm (PM_2.5), and ≤10 μm (PM₁₀), and nitrogen dioxide (NO₂), were estimated by validated spatiotemporal models. We used logistic regression models to examine the AP-MAFLD associations and further evaluated potential effect modifications by demographics, lifestyle, central obesity, and diabetes status. Increased exposure levels to all 4 air pollutants were significantly associated with increased odds of MAFLD, with odds ratios (ORs) of 1.13 (95% CI 1.10-1.17), 1.29 (1.25-1.34), 1.11 (1.09-1.14), and 1.15 (1.12-1.17) for each 10 μg/m³ increase in PM₁, PM_2.5, PM₁₀, and NO₂, respectively. Further stratified analyses revealed that individuals who are male, alcohol drinkers, and current and previous smokers, those who consume a high-fat diet, and those with central obesity experience more significant adverse effects from AP exposure than other individuals. This study provides evidence that long-term exposure to ambient PM₁, PM_2.5, PM₁₀, and NO₂ may increase the odds of MAFLD in the real world. These effects may be exacerbated by unhealthy lifestyle habits and central obesity. We conducted an epidemiological study on the potential effect of ambient air pollution on the risk of metabolic dysfunction-associated fatty liver disease (MAFLD) in approximately 90 thousand adults in China. We found that long-term exposure to ambient air pollution may increase the odds of MAFLD, especially in individuals who are male, smokers, and alcohol drinkers, those who consume a high-fat diet, and those with central obesity.

Little is known about the association between spicy food intake, dietary approaches to stop hypertension (DASH) score, and incident stroke. This study aimed to explore the association of eating spicy food, DASH score, and their interaction with stroke incidence. We included 22,160 Han residents aged 30–79 in southwest China from the China Multi-Ethnic Cohort. Three hundred and twelve cases were newly diagnosed with stroke by October 8, 2022, during a mean of 45.5 months of follow-up. Cox regression analyses showed that eating spicy food reduced stroke risk by 34% among people with low DASH scores (HR 0.66, 95%CI 0.45–0.97), while individuals with high DASH scores versus low DASH scores had a 46% lower stroke incidence among spicy food nonconsumers (HR 0.54, 95%CI 0.36–0.82). The HR of the multiplicative interactive term was 2.02 (95%CI 1.24–3.30) and the overall estimates of relative excess risk due to interaction (RERI), attributable proportion due to interaction (AP), and the synergy index (S) were 0.54 (95%CI 0.24–0.83), 0.68 (95%CI 0.23–1.14), and 0.29 (95%CI 0.12–0.70), respectively. Consuming spicy food seems to be associated with lower stroke risk only in people who have a lower DASH score, while the beneficial effect of higher DASH scores seems to be found only among nonconsumers of spicy food, and a negative interaction may exist between them in southwestern Chinese aged 30–79. This study could provide scientific evidence for dietary guidance to reduce stroke risk.

Background: It is true that Chronic obstructive pulmonary disease (COPD) will increase social burden, especially in developing countries. Urban-rural differences in the lagged effects of PM2.5 and PM10 on COPD mortality remain unclear, in Chongqing, China. Methods: In this study, a distributed lag non-linear model (DLNMs) was established to describe the urban-rural differences in the lagged effects of PM2.5, PM10 and COPD mortality in Chongqing, using 312,917 deaths between 2015 and 2020. Results: According to the DLNMs results, COPD mortality in Chongqing increases with increasing PM2.5 and PM10 concentrations, and the relative risk (RR) of the overall 7-day cumulative effect is higher in rural areas than in urban areas. High values of RR in urban areas occurred at the beginning of exposure (Lag 0 ~ Lag 1). High values of RR in rural areas occur mainly during Lag 1 to Lag 2 and Lag 6 to Lag 7. Conclusion: Exposure to PM2.5 and PM10 is associated with an increased risk of COPD mortality in Chongqing, China. COPD mortality in urban areas has a high risk of increase in the initial phase of PM2.5 and PM10 exposure. There is a stronger lagging effect at high concentrations of PM2.5 and PM10 exposure in rural areas, which may further exacerbate inequalities in levels of health and urbanization.

Hyperuricemia is associated with substantial health and economic burden all over the world. Dietary habits are an important influencing factor of hyperuricemia. This study aimed to investigate the relationship between spicy food intake and hyperuricemia based on a large population. A total of 22,125 individuals aged 30–79 were enrolled in China Multi-Ethnic Cohort (CMEC), Chongqing region. Spicy food intake information was collected by a standardized questionnaire. The association between spicy food intake and hyperuricemia was estimated by multivariable logistic regression models and multiple linear regression models. Additionally, we explored these relations in subgroups stratified by sex and age. Furthermore, sensitivity analyses were conducted to verify the stability of current findings. After controlling for potential confounders, compared with participants who never consumed spicy food and consumed less hot, participants who ate 3–5 days per week and very hot had the highest risk of hyperuricemia; the ORs (95% CIs) were 1.28 (1.09, 1.5) and 1.22 (0.92, 1.63), respectively. Additionally, the corresponding ORs (95% CIs) for each level increment in the frequency and degree of pungency in spicy food intake were 1.04 (1.01, 1.07) (P trend = 0.009) and 1.15 (1.04, 1.26) (P trend = 0.004). Further in sex-stratified and age-stratified analysis, similar positive associations were observed among men and those aged 30–59, but no significant association was found among women and those aged 60–79. In the linear regression models, 3–5 days per week and moderate pungency in spicy food intake were associated with 5.21 μmol/L (95% CI: 1.72, 8.70) and 4.69 μmol/L (95% CI: 1.93, 7.45) higher serum urate level. Results in further subgroup analysis were generally consistent with the logistic regression models. This study suggests that spicy food intake may be a risk factor for hyperuricemia, especially in men and younger people, and more studies are warranted to verify the causal associations.

Background: Although there are several cross-sectional and prospective studies on the relationship between sleep duration /insomnia symptoms and depression symptoms, the results of these studies are still not conclusive, and few studies have further analyzed the association between sleep duration and depressive symptoms in adults by gender and age. Thus, this study aimed to investigate the relationship between nocturnal sleep duration and insomnia symptoms with depression symptoms, and further examine whether the association was impacted by age and gender in a large-scale Han Chinese population in southwest China. Methods: A cross-sectional study was performed that included 44,900 participants from 18 districts in southwest China from September 2018 to January 2019. The study comprised 42,242 individuals in the final analysis. Depressive symptoms were investigated using the PHQ-2 questionnaires. Multivariate logistic regression analysis was performed to investigate the relationship between nocturnal sleep duration and insomnia symptoms with depression symptoms as well as the influence of age and gender. Results: After adjusting for multiple variables, those with nocturnal sleep duration < 7 h had a higher odds ratio for depression (OR:1.47, 95%CI 1.31–1.65) compared to participants whose nocturnal sleep duration was in the range of 7-8 h. Notably, there is a higher association in those aged below 45 years (OR:1.91, 95%CI 1.52–2.41) and in female participants (OR:1.57, 95%CI 1.35–1.82). However, nocturnal sleep duration longer than 9 h was not associated with depression symptoms in either the whole population analysis or the subgroup analysis. Insomniacs had a higher odds ratio for depression(OR:1.87, 95%CI 1.84–2.36, respectively) compared to non-insomniacs. There is a higher association in those aged 45–60 years (OR:2.23, 95%CI 1.82–2.73) and in female participants (OR:2.17, 95%CI 1.84–2.56). Further subgroup analysis by age and gender at the same time showed the association between sleep deprivation and depression was highest among women aged below 45 years, while the association between insomnia and depression was the highest among men aged 45–59 years. Conclusion: Short nocturnal sleep duration and insomnia symptoms were positively associated with the risk of depressive symptoms among Chinese Han adults aged 30–79 in Southwest China, especially the middle-aged population and females should be more concerned.

Background: Few animal experiments and volunteer-based intervention studies have showed a controversial effect of spicy foods on abdominal obesity. We aimed to examine the association between spicy food frequency, spicy flavor, and abdominal obesity among Chinese Han population in the Sichuan Basin which area eating spicy foods relatively often.Methods: A cross-sectional analysis was conducted using the Sichuan Basin baseline data from the China Multi-Ethnic Cohort (CMEC) study, including data from electronic questionnaires, anthropometric measurements and blood sample collection. A total of 40,877 adults (22,503 females) aged 30–79 years were included in the final analysis. Multivariable logistic regression yielded adjusted odds ratios (ORs) and 95% confidence intervals (CIs) for abdominal obesity associated with the strength of spicy flavor and frequency of spicy food intake.Results: The prevalence of daily spicy food eating was 47.3% in males and 52.7% in females, the percentages of abdominal obesity were 52.3%, 48.8%, 51.6% and 55.5% in the spicy food intake subgroups of never, 1–2 days/week, 3–5 days/week and 6–7 days/week, respectively. Compared with males who never consumed spicy food, the adjusted ORs (95% CIs) in the 1–2 days/week, 3–5 days/week and 6–7 days/week subgroups were 1.21 (1.09, 1.34), 1.35 (1.21, 1.51), and 1.35 (1.25, 1.47), respectively (P_trend < 0.001). The corresponding odds ratios for females were 0.95 (0.87, 1.05), 1.14 (1.03, 1.26), and 1.25 (1.16, 1.35), respectively (P_trend < 0.001). Similarly, compared with no spicy flavor, the adjusted ORs (95% CIs) of mild, middle, and strong spicy strength for abdominal obesity in males were 1.27 (1.17, 1.38), 1.51 (1.37, 1.67), and 1.36 (1.11, 1.67) respectively (P_trend < 0.001). The corresponding odds ratios for females were 1.14 (1.06, 1.23), 1.27 (1.15, 1.40), and 1.32 (1.06, 1.65), respectively (P_trend < 0.001).Conclusions: The data indicated that spicy food consumption was a risk factor for abdominal obesity among Chinese adult population in the Sichuan Basin. The results need to be approved by large cohort studies.